Background Dog ownership has been associated with higher rates of physical activity (PA) in several populations but no study to date has focused on cancer survivors. The purpose of this study was to examine the associations between dog ownership and PA among cancer survivors and to examine correlates of dog ownership. Methods A stratified random sample of 2062 breast cancer survivors, prostate cancer survivors, and colorectal cancer survivors was mailed a questionnaire assessing PA, social cognitive, dog ownership, demographic, and medical variables. Results Overall, 25% of the sample was dog owners (DOs). There were no significant differences in moderate, vigorous, or total PA minutes between DOs and non–dog owners. There was a significant difference in light PA minutes in favor of DOs (153 vs 112 minutes; 95% CI = 4 to 77; P = .030), however, this was largely restricted to breast cancer survivors (143 vs 79 minutes; 95% CI = 25 to 102; P = .001) who also reported fewer vigorous PA minutes (18 vs 39 minutes; 95% CI = −42 to −1; P = .042). Survivors were more likely to be DOs if they had breast cancer (P = .054), a higher income (P = .021), radiation therapy (P = .029), chemotherapy (P = .010), were younger (P < .001), employed (P < .001), and a current smoker (P = .015). Few social cognitive variables were associated with DO. Conclusions Dog ownership among cancer survivors was not associated with moderate‐to‐vigorous PA but was associated with light PA. Further research is necessary to determine if promoting dog ownership and dog walking among cancer survivors may increase PA and possibly improve health outcomes.